Detection of H2-b and Thy-1.2 surface antigens on the differentiating murine otocyst using Nomarski optics

The 12th postcoital day otocyst appears as a hollow cellular ball of pseudostratified columnar epithelium that has entered into its inital stages of differentiation and organogenesis. H-2b antigen was demonstrated on the ectodermally derived epithelial cells of the otocysts and on the mesodermally derived cells of the surrounding mesenchyme. Thy-1.2 antigen was detected in the mesenchymal cells, but not on the epithelial cells of the otocyst. The use of Nomarski optics as a new method for detecting cell surface staining that would otherwise be undetected by bright field optics was demonstrated.